Perhaps the most agonizing bit of ill fortune befell Zulkhumar Muminova and Nasibullo, her 3-year-old boy. He almost made it.

Ms. Muminova said she and the child survived hours of violence last Friday when the government of Uzbekistan used gunfire to disperse a prison break and antigovernment rally in the city of Andijon. And she said she managed to keep together with the boy and her four other children during an all-night trek toward the Kyrgyz border.

But just short of safety, she and several witnesses said, the Uzbek authorities fired on them anew. ''All the people ran in different directions,'' she said. ''And I lost him, my son. I have not seen him again.''

Five days after an outbreak of violence consumed Uzbekistan's Fergana Valley, the greatest challenge to the credibility and public stature of Islam A. Karimov, the authoritarian president of Uzbekistan, can be found here among the survivors, who live in 10 tents in a ravine a few hundred yards above the muddy Karadariya River.

There are 540 Uzbek refugees registered in this camp. It is a group stalked by uncertainties and memories of horror, and crowded with people who accuse Mr. Karimov of lying to the world.

Mr. Karimov said on Tuesday that 32 soldiers and 137 other people had died in the violence last week, and insisted that the authorities did not fire on women or children. In lengthy interviews, however, the survivors say the number of dead was much higher, and tell another story of the authorities' conduct.

They say that in the morning after armed men stormed the Andijon prison to free 23 businessmen that the demonstrators thought were unjustly accused of religious extremism -- and 2,000 other inmates -- the Uzbek government abruptly cut off negotiations with what had become a swelling antigovernment revolt.

Then, the survivors said, the authorities raked the crowds with fire from machineguns mounted on armored personnel carriers, while snipers on at least two nearby buildings shot down with precision rifle fire.

An odyssey ensued, the refugees say, as a mass of survivors fled in a shrinking group northward, dropping off their wounded or those who could not go on at homes along the way, until they almost reached the Kyrgyz border. Then, they said, the Uzbek troops briefly fired on them once more.

At last the weary survivors negotiated their passage across the river with a compassionate regional official, they said, and came to rest here, in the dust and grass.

Some said they were still in a state of disbelief. ''Have all of our soldiers become robots?'' asked Ms. Redzhapova, 36. ''They just follow orders? An old man was killed. We saw it. An invalid was killed. We saw it. They just follow orders?''

Around her, the camp pulsed with worry and emotional shock.

Some said they saw bullets strike their husbands or wives, and then did not see them again. Others, like Ms. Muminova, became separated from their children, and have no idea of their whereabouts now. Was Nasibullo picked up by soldiers? Was he left to wander in the fields?

Mr. Muminova scanned across the river and the Uzbek barbed wire, to where the boy had been. She did not know.

There are 96 women and children among those in the camp. The oldest refugee is 76 years old. Rhakhima Gofurdzhanova is the youngest. She is a year old.

Their fears have assumed many forms. Many survivors said they fled so hastily that they left behind family members who had not been demonstrating on the square, as did Ms. Muladzhanova, Ms. Jumabayeva and Ms. Redzhapova. All of these people said they now worry that the Uzbek authorities will round up their relatives for reprisals.

Tursunbai Nazarov, 47, one of the 23 businessmen who had been on trial, emerged from a tent looking haggard and weary, the result, he said, of 11 months in prison and seven or eight sustained beatings he suffered during interrogations.

He had been freed in the prison break last week. Now in Kyrgyzstan, he said his wife, son and daughter remained in Andijon, and said he worried for their lives.

''The powers know my address, and may well go to my home at any time,'' he said.

Like claims by the Uzbek opposition that as many as 745 civilians were killed last week, the accounts of survivors, while largely consistent with one another, could not be independently confirmed, in part because the Uzbek portion of the Fergana Valley is still almost entirely closed to unrestricted travel by outsiders.

The survivors also moved quickly past any discussion of culpability among some members of the antigovernment ranks. Many admitted, for instance, that the protestors were armed last Friday and took hostages, but they also insisted that no one who carried a weapon or committed a crime is among the refugees in Kyrgyzstan.

Virtually everyone here called for the removal of Mr. Karimov, whose government has been criticized for years for rigging elections, suppressing personal freedoms, persecuting opponents and Muslims who practice their faith out of state-sanctioned mosques, and systematically using torture.

''Our president has to resign,'' said Uktom Turanov, 29, a welder.

People here also called for an international investigation and trial of those culpable for what they called a massacre. Uzbekistan, they said, cannot go forward until the matter is resolved.

The demand was echoed on Wednesday by Britain's foreign secretary, Jack Straw, who said on BBC that official Uzbek explanations have been inadequate, and demanded that an ''international and independent inquiry'' examine the circumstances surrounding the crackdown.

''It is of crucial importance for the stability of society in Uzbekistan, as well as for the credibility of the government in Uzbekistan, that we get to the bottom of what happened,'' he said.

The United Nations high commissioner for refugees also said an investigation was necessary.

United States officials expressed concern and called for more openness. ''We know that the American side cooperates with Uzbekistan; they are allies,'' said Khassan Shakirov, 27, who said his brother was killed in Andijon when an Uzbek security official shot him in the back. ''But we think that after this tragedy, Americans should think twice before cooperating. Let their souls make a judgment.'' The United States maintains a military base in Uzbekistan, and has collaborated with Mr. Karimov in counterterrorism efforts.

Gen. John P. Abizaid, the top American commander in the Middle East and Central Asia, said Wednesday that the United States had curtailed its operations at the Khanabad air base in Uzbekistan.

In an interview with reporters in Washington, he said the move was intended to protect American forces. ''It's not designed to be a political statement at all,'' he said.

A spokesman at the American Embassy in Bishkek, the Kyrgyz capital, said the embassy had provided $50,000 to the Paris-based Agency for Technical Cooperation and Development, a nongovernmental agency, to provide food for the refugees. ''That amount should be enough for about two months if the number of refugees doesn't increase,'' the spokesman said.

Rice, tea and bread were in the camp on Wednesday, as was soap. Since arriving Saturday morning, the refugees have also been given blankets to cover dirt floors of the tents and, in many cases, clothing.

What will happen to these refugees remained an open question. The camp was under Kyrgyz guard, both to protect the refugees and to prevent them from leaving. Officials said Uzbekistan might ask for them to be returned.

''The Uzbek side says we can keep them here for 10 days, and within 10 days the Uzbek authorities will decide their fate,'' said Lt. Col. Pizulla Kendzhabayev, of Kyrgyzstan's Ministry of Emergency Situations, who watched over the crowd.

Photo: Residents of the Uzbek village of Karasu at the Kyrgyzstan border yesterday. United Nations officials called for the border to remain open. (Photo by Maxim Marmur/Agence France-Presse -- Getty Images)

Map of Kyrgyzstan highlighting Karadariya: Uzbeks sought safety in Karadariya, on the border with Kyrgyzstan.